Traffic recorder for telephone systems



M'. SCHWARTZ- TRAFFIC RECORDER FOR TELEPHONE-SYSTEMS or'iginaiFiled July 12.. 1922 2 Sheats-Sheet 2 Patented May 1, 1928.

UNITED STATE MIGHAEL SCHWARTZ, OF CHICAGO, ILLINOIS, ASSIGNOR,

s PATENT OFFICE.

BY MESNE ASSIGNMENTS, T0

AUTOMATIC ELECTRIC INC., 'OF CHICAGO, ILLINOIS, A CORPORATION OF DELA- WARE.

TRAFFIC. RECORDER FOR TELEPHONE SYSTEMS.

Application filed July 12, 1922, Serial No. 574,494. Renewed August 4, 1926.

The present invention relates in general to trailiorecord-ers for telephone systems. More specifically, the invention is concerned with devices which record the traffic on trunks extendin between automatic switches.

An ob ect of the invention is to provide a recording'device for registering the numher of times a trunk line is seized and then released within a very short interval, together with means for registering the nunr her of times the trunk line is used for alonger interval as for a successful call to a called line.

Another object of the invention is to provide a device for registering the total length of time the trunk line is in use.

Another object of the invention is to reg ister the number of times allthe trunks in a group become busy, and also to record the total'length of time that this all trunk busy period lasts.

Still another object of the invention is to provide means for at all times showing the number of simultaneous connections over the group of trunks under observation.

A further object of the invention is to provide an improved timing device, where by the recordingmechanism may be controlled at various speeds.

There are other objects of the invention.

which have not beennientioned. but which, together with those enumerated above, will be described hereinafter, reference being had to the accompanying drawings. 4

Referring now to the drawings, comprising Figs. 1 and 2, there is shown suflicient apparatus involving the invention to enable the same to be readily described and understood.

Referring now more 'iarticularly to Fig. l, in the upper portion of the drawing; des ignated by the reference character E, an automatic selector switch of the usual Strowger type, the construction. and circuits of which are well understood.

' At A is indicated a. recording milli-ain meter for registering the total number of simultaneous calls in the group of trunks under observation. This milli-ammeter may be of any well-known or desired type.

The traflicrtacording device proper consists of the equipment designated by the reference characters M and M. The equipment shown at M consists merely of a group sired to merely register the total number of calls over a trunk line, and the total length of time the trunk is'held in use. In the present instance it will be assumed that it is desired to record the trafiic on a group of ten trunks. In this case, each trunk line will have individual to. it apparatus such as M and M. Thus. the equipment M and M is individual to the trunk line comprising conductors 10-12, inclusive, with the exception of the meters 89 and 102. The meter 89 is common to the ten trunk lines of the group and serves to register when all trunks become busy. The meter 102 is likewise common to the ten trunk lines and. registers cumulatively the total length of time all ten trunks are in use.

The recording apparatus including the equipment M and M may be used to record the traffic on a trunk line extending from a line switch to a first selector, a selector trunk line, or in fact. any kind of trunk over which it isdesired to record the trafiic.

In 2, there is shown the timing mechanism. This is common to all the trafiic recordingdevices of the exchange, and comprises essentially a constantly operating timing device P and two rotary switches C and S. The rotary switch S is of very simple construction and comprises wipers 180. and 181. an operating magnet 168 and a release magnet 169. The rotary switch C. whose wipers move in a forward direction only, is of the same general mechanical construction as the well-known rotary line switches.

Having brifiy described the apparatus shown in the drawings, a detailed, description oi its operation will now be given. For thispurpose. it will be assumed that the trunk line comprising the conductors 10-12, inclusive. is seized by another selector switch or by a line switch under the control of a calling subscriber. Immediately upon the subscribers line being extended to the line relay 15 of the selector E, this relay is en ergized. Upon operating, relay 15, at armaturc 20, closes the circuit of the slow acting relay 16. The latter relay, upon energizing, at armature 21. prepares the operating circuits of the selector E. and at arn'iatiu'e 22:

places ground upon the release trunk conductor 11, thereby establishing a holding circuit for the preceding switch or switches.

The calling subscriber may now operate his calling device in accordance with the next digit in the desired number. By this operation a series of interruptions is produced in the circuit of the line relay 15 of the selector E, which deenergizes a. plurality of times in response thereto. At each retraction ofthe armature 2t) ot the line relay 15, an impulse of current is sent to the ver tical magnet. 16 in series with the slow acting relay 17 The vertical magnet 4-6. opcrates to raise the shaft of. the switch carrying the wipers 3543?, inclusive, step by step until the said wipers are brought opposite the proper level of bank contacts The slow acting relay 1'? is energized in series with the vertical magnet, and main tains its armature attracted throughout the vertical movement. of the switch. Upon the first verticaLstep of the switch shafhthe relay 17'being now energized, a circuit is completed for the stepping relay 18. Upon operating,.relay 18 establishes a locking circuit for itself at its upper armature, and at its lower armature prepares a' circuit for the rotary magnet 1 1. Shortly after the end of the vertical movement, the slow acting relay 17, deenergizes to close the circuit of theretary magnet 44. The magnet 44:, operates to advance the switch wipers into engagement with the first set of bank contacts in the selected level, and also opens the locking circuit of the stepping relay which deenergizes, opening the circuit of the rotary magnet which deenergizes also. If the trunk line with which the switch wipers are now in engagement is busy, the stepping, relay 18 will again be energized "from ground upon the test contact of the associated trunk line. Relay 18. upon operating, com 'ilctcs a lock ing circuit for itself and also closes the rotary magnet circuit. The rotary magnet opcrates to advance the wipers of the switch into engagement with the next set of'bank contacts and opens the circuit of the stepping relay. The stepping relay decnergiZes to open the circuit of the rotary magnet, which also deencrgizes. The alternate operation of the relay 18 and'the rotary magnet 44 continues until the wipers of the selector E are rotated into engagement with a set of bank contacts associated with an idle trunk line, which, we will assume. are the bank cont-acts 3840, inclusive. 'When the Wipers 35-37, inclusive, are brought into engagement with this set of bank contacts, the

rotary movement of the selector E ceases, and the switching relay 19, which during the preceding operations of the switch has been short circuited, is energized in series with the stepping'relay 18. Relay 1 9 o 1 cratesto extend the calling line over the wipers 35 and 37, bank contacts 38 and 41), trunk conductors 11 and 13, to the windings ot the line relay of the seized switch.

The line relay of thc select-ed switch immediately ei'iergizes to close the circuit of its associated slow acting release relay. The latter relay operates to prepare the circuits of the seized switch for operation, and to place ground upon the release trunk. 42 to establish a holding circuit for. the selectorv E and the preceding switch or'switches.

The further extension of the connection.

in response to the remaining digits dialled by the calling subscriber will take place in the usual'manner, and as this extension does not concern the present invention, it will:

be not described herein.

It will be noted that as soon as the selector E is seized. ground is placed upon the release trunk conductor 11, and a. circuit is complctcd extending tronrt-his ground over conductor 13, terminal of the recording device M, through the resistance 60, and through the recording inilli-annneter A to battery. The current flowing through the resistance and the winding of the milliainmeter affects the marking pen in the usual manner, causing the line on. the chart to be raised a suitable distance to indicate another call. All the release trunks of the group oi trunks are connected through a resistance similar to 60 to the recording milli-an'nncter so that the reading of the milli-annnetcr is always proportionate to the number of simultaneous calls in the group. The resistanccs, such as 60, are sufficiently high so that there is no interference by aground potential being extended through these rcsistances to the other release conductors of the trunks of the group when one or more become busy. There is also another circuit completed by the grounding ot conductor 11, which. extends from terminal 50 by way of terminal 51. working contact ot springtiil of key K and the said spring, this key being in operated position when it is desired to recordthe traflicon the associated trunk. terminal 52, terminal Through the wind.- ing of the high resistance relay 70, through the winding of the low: resistance relay 71, terminals 56 and 53, and through the winding of the meter magnet. 100 to battery. Only thehigh resistance relay 7,0 is operated over. the above circuit." Upon attracting its HIIYIH DUTPS TOlfLY 70, at armature 76 closes a circuit which extends troinground by. Way of the front contact'oi armature 76 and the said, armature, terminals 57 and 5 b working contact of spring 61 and the said Hit" Ill)

spring, through the winding of the meter the timing device is being connected to bat tery once every second by the operation of the timing mechanism, as will be described, and consequently, the meter magnet 101 is operated to register every second, thus indicating by its cun'imi'llative registration for various calls the total length of time that the trunk is held in, use. Further results of the energization of relay 70 are that at armature 77 a circuit is prepared for the release magnet 7 41 of the minor switch S, at armature 78 a point is closed in a certain chain circuit, which will be described, and at armature 79 the rotary magnet 73 of the rotary switch S is connected over conductor 110 to the terminal 164 of the timing device. The terminalltit of the timing device is being momentarily connected to battery once every half second, as will appear later, and consequently, the motor magnet78 operates to advance the wiper 95 one step every half second. At the end of four seconds, the wiper 95 is advanced into engagement with the bank contact 96, whereupon the winding of the relay 7 0 is short circuited. By this operation relay 71 and the meter magnet 100 are energized. Upon operating, relay 71, at armature 80,-establishes a looking circuit for itself exclusive of the wiper 95, at armature 81 closes a new circuit for the meter 101, atthis same armature closes the circuit of'the slow acting relay 93, at armature 82 closes a circuit ilorthe release magnet 74 of the minor switch S. at armature 84L closes a new point in the chain relay above mentioned to provide against the deenergization of relay 70, and at armature 85 transfers thecircuit ofthe motor magnet 73 of the minor switch S from connection with the terminal 164:, into connection with the terminal 165 of the timing device. As the winding of relay 7 0 has been short circuited by the operation of wiper 95 Of the switch S, this relay will deenergize. However, due to the fact that it'is short circuited, it will be made slow acting and maintain its armature attracted for a short interval after the short circuiting of its winding. long enough to alow the minor switch S to be released. The operation of the meter 100 serves to register one call. The slow acting relay 93. upon operating, at armature 87 opens a point in the circuit of relay 72, and at the front contact of this armature prepares a circuit for the release magnet 74. As the motor magnet 7 3 of the minor switch S is now connected to the terminal 105 of the. timing device, it will be operated once every seconds- Each time the magnet 73 operates it advances the Wiper 95 one step. At the end of 500 seconds, the Wiper 95 will engage the bank contact 97, whereupon, if

the connection is not terminated, the lan'ip L will be lit. The operation of the lamp L,

serves to notify the attendant at thee change that the particular trunk having the equipment M has been in use for a. prolonged period of time. The attendant may now examine this trunk to see if it is held due to some unnatural condition.

It will be remembered that the relay 71, upon operating. closes a point in a certain chain circuit. This circuit includes contacts on other relays, such as relays and 71, in other equipment such as M- which are associated with the other trunks of the group. lVhen all the trunks of the group become busy, the chain is closed, and the meter magnet 89 will be operated to indiate this fact.

It will be noted that each time the timing meter magnet 101 operates, the armature 106 is caused to engage its working contact. This armature andcontact is included in another chain circuit which has contacts on various other magnets, such as 101 in the groups of ten trunks with which these meters are associated. When all the trunks of this group of ten become busy, the meter magnet 102will be operated to denote by its cumulative operation-the time that these trunks are held in use. 1

Should it happen that, when the trunk line comprising conductors 1042, inclusive. is first seized, the subscriber should replace his receiver before the wiper advanced into engagement with the bank contact 96,

the meter magnet l00'would not be operated. However, when the connect-ion is released, the relay 70 will be deenergized, while the minor switch S will be off normal. The slow acting relay 72 is accordingly energized in series with the release magnet 74, and operates at its armature 86 to close the circuit'ot the meter 88. Meter 88 operates once to register that the trunk line has only been used for a short period of time, less than four seconds, while magnet 7 loperates to restore the minor switch S to normal.

W hen the connection is released, ground is retrieved from the test contact 39 with which the test wiper 30 of the selector E is in engagement, and the selector E is released in the usual. manner. When ground removed from the release trunk conductor 11. the relay 71 in the metering equipment M deenergized. By the deenergization oi": relay 71, the circuit oi. the slow acting relay 98 is opened. After the deencrgizae tion of relay 71 and before the deenergization of relay 93. a circuit is completed for the release 1118,2119.) 7 4 over a path extending from ground by way of front contact and armature87. armature 83 and its back contact, back contact and armature 77 of? normal spring and its working contact, and through the winding of the release magnet 7 4.; to cattery. Accordingly, the minor switch's' is released. Another result oi the dcenergizationof relay 71 is that the circuit of the. timing meter 101 is opened at arma- 1 ture 8l. The-operation of the other contacts on the relay 71' serve merely to restore certain circuits to normal.

Having described the operation ot the metering device when the equipment Ill. is used, its operation whenonly the equipment- M is used will now be described. In this case, all the terminals 56-54. inclusive, will be connected together. Now. when ground is placed upon the release trunk conductor 11. at the time the trunk is seized, the meter magnet- 100is immediately operated to register one connection, and the timing meter 101 innnediately starts to operate. The current flowing through the resistance 60, of course, causes the milli-ammeter A. to 'ister another connection. When the connectionis released the selector E is restored to norinal and the equipment M ceases functioning.

The operation of the timing device shown in Fig. 2 will now be described. The device 1 consists of a constantly operating pendulum 150, which is controlled by the relay 151. Its-operation isas follows lVhen the pendulum. swings to the left, it closes the springs 150 and 156,v whereupon a circuit is completed tor the relay 151-. llpon cncrg iing g, relay 151 attracts its armature As the tension is taken off spring 156, this spring operates and causes the pendulum spring 150 to be forced to the left, therehy moving the pendulum to the right. IV ion the pendulum swings to the right, it opens the circuit of the relay 151, which deenergizes, causing the spring 156 to assume its normal position. The same operation is then repeated. An additioinal result of the energization of the relay 151 is that at armature 152 battery is connected to the conductor 157. which extends through the stepping magnet 167 of the rotary switch C to ground. The weight on the pendulum 150 is so adjusted that the relay 151 is energized once every half second. The terminal 16d of the timing device thus has battery placed upon it once every halt second. The stepping magnet 167 is operated once every half s cond and serves to advance the switch wipers 17:?178, inclusive, one step every half second. In the contact banks adapted to be engaged by wipers 175 and 17 6, the contacts are tied together alternately. In the bank adapted to be engaged by wiper 175, the first, third, and other odd contacts are connected together and to the terminal 163. In the contact bank adapted to be engaged by wiper 176, the second, fourth, and other even contacts are connected to the teri'ninal 163. The wipers 175 and 176 are set opposite each other so that when the wiper 17 5 engages the first bank contact, the wiper 176 leaves the twenty-fifth bank contact. By this arrangement the conductor leading to the: terminal 163 connected to battery once every two steps of the wipers 175 and. 176.. Int-heront t bank adapted to he engaged. by wiper. 177. every tilth contact is connected together. and thence to the terminal 162.. Thus, the terminal. 162 is connected to battery once every two and one-halt. seconds. Only one contact in the bank adapted to be engaged by wiper 178 is connected to the terminal 160.. Another contact is connectedto the terminal.

161. Thus, the terminals 160 and 161. are

connected to battery once every twenty-five seconds. that is, each fifty steps of the wiper 178. The space between the battery impulses at the terminals 160 and 161 is determined by the space between the bank con? tacts to which these terminals are connected in the bank .adaptedtto he engaged by wiper its twenty-fifth bank contact. closes the circuit ot the stepping magnet 168 of the minor switclrS. Magnet 168 operates to advance the wipers 180 and 181 one step every. twenty-five seconds. As alternate contacts in the bank of wiper, 180 are connectedtogether andto the. terminal 165, this terminal is connected to battery onceevcryv fifty seeonds. hen the wipers 180and 181 reach their tenth position, the next time the wiper 178 engages its twentieth bank contact, the slow acting relay 170 is energized. Relay 1.7 0 operates to close the circuit of the release magnet 169. Magnet 169 operates to restore he minor switch S to normal, whereupon the same operationis repeated. In this manner battery is connected. to the terminal 164 every one-half second, to the terminal 163v every second, to theterminal 162 every two and one-half seconds, to the terminals 160 and 161 every twenty-five seconds, and to the terminal 165 every fifty seconds, whereby the traflic recording devices are controlled as has been described. Terminals 160, 161 and 162 are provided to make it possibe to change the rate of operation of time controlled mechanisms of the recording equipment. These terminals may. also be utilized in operating other apparatus at the exchange requiring a different rate of operation than could be obtainedby connecting with any of the terminals 163. 164, or 165.

What I claim is:

1. In a telephone system, a trunk line, means for making said trunk line busy, a. metering device, andmeans responsive to the busy condition of said tr-unkline for operating said device only if said trunk line is held in use a. predetermined period.

2. In a telephone system, a trunk line, means for making said trunk line busy. a metering device, means responsive to the busy condition of said trunk line for operating said deviceif said trunk line is held in use 18. In additiointhe wiper 17.8 inengaging apredeterminedperiod,. and means for preventing the operation off said device ifsaid trunk lS-gllld in use for; a lesser period of time h a 3(111 telephone system, atrunk line, means for making said. trunk line busy, two

\ registering devices, and means responsive to the busy condition of said trunk line for operating one device if said trunk line is held a predetermined time and for operating the other device'if said trunk'line is held less than said predetermined time.

l. In a telephone system, trunk line, means for making said trunkline busy, an automatic switch associated with said trunk line, an operating magnet for said switch, a

circuit for said magnet, a meter, means responsive to the busy condition ofsaid trunk line r01- periodically closing said circuit when said trunk line is in use, and means controlled by the operation of said switch to opcrate said meter.

5. In a telephone system, a groupof trunk lines, means for making said trunk lines busy, a register for recording the number of times all trunks of thegroup arebusy, means responsive when all trunks are busy for opcrating said register,,and means for recording the cumulative time during which said all trunk busy conditionexists.

6. In a telephone system, a group 015' trunk lines for use in establishing talking connections, and means associated therewith responsive to the use of said trunk lines'i'orat all times showing the number of trunks simultaneously in use.

7. In a telephone system, a trunk line, means for making said trunk line busy, an eleetromagnetically actuated device for registering the total length of time said trunk is in use, and a current supply and associated circuits responsive to the busy condi tion of said trunk line for operating said registering device as set forth.

8. In a telephone system, a trunk line, means for making said trunk line busy, separate means both responsive to the busy condition of said trunk line for making records of the number of times the trunk becomes busy and the cumulative time the busy condition exists, and means also responsive to said busy, condition for giving an alarm should the trunk remain busy for an unusually long period.

9. In a telephone system, a trunk line, a line switch, means responsive to a calling subscriber removing his receiver for causing said line switch to seize said trunk line and make said trunk line busy, a register for recording the number of incompleted calls, and means responsive to the calling subscriber hanging up his receiver before completing his call for operating said register.

10. In a telephone system, a group of trunk lines, means for making said trunk lines busy, a register associated with each of said trunks? foiVrec'ordingf the number of times theassoc'iated trunk is busy, a second register associated with eachof said trunks for recording the cumulative time the assoeiated trunk is busy, athird' 'register for recording the number of times alltrunlrs of the group are busy, a fourth register for recording the cumulative time during which said all trunk busy condition exists, and means responsive to the busy condition of said trunk linesfor operating said registers as setforth. i

11. In a telephone system, a group of trunk lines, means rot making all of said trunk line busy, and means responsive to an all trunk busy condition for recording the cumulative time during which said allfltrunk busy condition exists. i I

12. In a telephone system, trunk line, means formaking said trunk line busy, a register, a circuit for said register, and means responsive to the busy condition of said trunk line for intermittently interrupting said circuit to intermittently operate said register to register the total length of time said trunk line is in use. i

13. In a telephonesysteinfa trunk line, means for making said trunlrline busy, an automatic switch associated with said trunk line, a meter for registering the number of times said trunk lineis taken intense, means responsive to the busy condition of said trunk line for operating said switch a plurality of steps, and means for operating said meter only after said switch has taken a predetermined number of steps.

l i. In a telephone system, a series circuit includingone conductor of a trunk line, a relay and a meter, said relay being operated over said circuit when said trunk line becomes busy, an automatic switch, means controlled by said relay for closing a circuit to cause the operation of said switch, and

means controlled by said switch for short circuiting said relay to cause the operation of said meter.

15. In a telephone system, a series circuit including one conductor of a trunk line, a pair of relays and a meter, only one of said relays being operated over said circuit when 7 said trunk line becomes busy, an automatic switch, means controlled by said operated relay for closing a circuit to cause the operation of said switch, means controlled by said switch for short circuiting said operated relay to cause the operation of said other relay and meter, and means controlled by thesaid other relay for releasing said switch. t

16. In a telephone system, a trunk line, apparatus for recording the number of times and the total length oi time said trunk line is in use, said apparatus being normally disconnected from said trunk line, and a manually operated device'for operatively associating said apparatus with said trunk line at Will.

17. 'In a telephone system, a trunk line, apparatus for recording the number of times and the total length of time said trunk line is in use, said apparatus being'normally disconnected from said trunk line, a third conductor of said trunk line, and a key for operatively associating said conductor With said apparatus for recording purposes.

18. In a telephone system, a group of trunk lines, a device for registeringthe total number of simultaneous calls in said "group, a release conductor for each trunk line or" said group, and connections extending from said device to each of said conductors for operatively associating said device with all of the trunk lines of said group.

19. In a telephone system, a trunk line, means for making said trunk line busy, a register, means for removing the busy condition from said trunk line, and means operative in case said lousy condition exists for less than a predetermined time for operating said register.

20. In a telephone system, a trunk line, means for making said trunk line busy, a

register for recording the number .ofincompleted calls, means :for removing the busy condition from saidtrunk line, arelay operative responsive to the removal of said busy condition if the same occurs before a predetermined time has elapsed, and contacts on said relay for closing a circuit to operate said register.

21. In a telephone system, a roup of trunk lines, a register, .a circuit or operating said register, means for closing said circuit when all said trunk flines become busy and means for intermittently and'automatically interrupting said circuit thereafter to cause said register to indicate the time during Which the all trunk busy condition exists.

22. In combination,'twoidevices, an auto matic progressively movable switch adapted to cause the operation of said devices, 'respectively, responsive 'totWo successive operations of the switch, and means "for automatically changing the speed of the switch after the first operation thereo'f.

In "Witness whereof, I hereunto subscribe my name this sixth day of'Ju'ly, "A. 1).,

MICHAELSGHWARTZ. 

